Psoroptes spp. (1) Flashcards
What are the hosts?
Sheep
Goats
Cattle
Horses
Rabbits
How do you identify?
Up to 750 micro m
Pointed mouthparts for piercing and chewing
Nonburrowing
Oval
Causes “scab” mange
Pretarsi/pedicels
- Long - Segmented - Funnel-shaped suckers
What are the sites of infection?
Dorsum from shoulder to head
Areas that are well covered by wool/hair
Skin
Distribution on animal depends on season
- Reservoir sites during non-winter months - rapid spread in winter
Describe the Pathogenesis
Remains at base of hairs
Pierces skin with mouthparts
Exudate on of skin - hardens to form scab
Psoroptic scab
- Devastating in sheep - especially those maintained for wool
production
Lesions may cover almost the entire body
- Secondary bacterial infection common
Decrease production
Increased susceptibility to other diseases
Apparently healthy sheep may still carry small populations
Essential that this mite be differentiated from Chorioptes bovis
- Based on sucker shape at end of segmented stalk and shape of
mouthparts
Zone of inflammation with serous exudate
Dry crust covered center develops with moist borders
Describe the Pathogenesis of Psoroptes ovis
Highly contagious
Economically important
Skin disease in ruminants
Very serious - reportable form of mange in cattle, sheep, and horses
In US
- Affecting sheep - Eradicated - Bovine Strain diminished
What are the clinical signs?
Ragged wool
Intense Pruritis
Restlessness
Biting
Scratching
Death
Weight loss
How do you diagnose?
Skin scrapings
Clinical signs
Season
How do you treat and prevent?
Both acaricidal treatment and either disinfection or 2-4 weeks vacating of contaminated enclosures and vehicles
Official dips
- 2 Organophosphates, hot lime sulfur, MCLs
- Psoroptic scabies should be reported to state disease control
authorities and treatment carried out under supervision
What are the common names?
P. ovis - Sheep scab mite
P. cuniculi - Ear canker mite
